/*
 * Copyright (c) [2019-2020] Huawei Technologies Co.,Ltd.All rights reserved.
 *
 * OpenArkCompiler is licensed under Mulan PSL v2.
 * You can use this software according to the terms and conditions of the Mulan PSL v2.
 * You may obtain a copy of Mulan PSL v2 at:
 *
 *     http://license.coscl.org.cn/MulanPSL2
 *
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR
 * FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PSL v2 for more details.
 */
#ifndef METADATA_LAYOUT_H
#define METADATA_LAYOUT_H
#include <cstdlib>

// metadata layout is shared between maple compiler and runtime, thus not in namespace maplert
// some of the reference field of metadata is stored as relative offset
// for example, declaring class of Fields/Methods
// which can be negative
#ifdef USE_32BIT_REF
using MetaRef = uint32_t;      // consistent with reffield_t in address.h
#else
using MetaRef = uintptr_t;     // consistent iwth reffield_t in address.h
#endif // USE_32BIT_REF

// DataRefOffset aims to represent a reference to data in maple file, which is already an offset.
// DataRefOffset is meant to have pointer size.
// All Xx32 data types defined in this file aim to use 32 bits to save 64-bit address, and thus are
// specific for 64-bit platforms.
struct DataRefOffset32 {
  int32_t refOffset;
  template<typename T>
  inline void SetDataRef(T ref);
  template<typename T>
  inline T GetDataRef() const;
  inline int32_t GetRawValue() const;
  inline void SetRawValue(int32_t value);
};

struct DataRefOffsetPtr {
  intptr_t refOffset;
  template<typename T>
  inline void SetDataRef(T ref);
  template<typename T>
  inline T GetDataRef() const;
  inline intptr_t GetRawValue() const;
  inline void SetRawValue(intptr_t value);
};

struct DataRefOffset {
#ifdef USE_32BIT_REF
  DataRefOffset32 refOffset;
#else
  DataRefOffsetPtr refOffset;
#endif
  template<typename T>
  inline void SetDataRef(T ref);
  template<typename T>
  inline T GetDataRef() const;
  inline intptr_t GetRawValue() const;
  inline void SetRawValue(intptr_t value);
};

struct MethodFieldRef {
  // MethodFieldRef aims to represent a reference to fields/methods in maple file, which is already an offset.
  // also, offset LSB may set 1, to indicate that it is compact fields/methods.
  enum MethodFieldRefFormat {
    kMethodFieldRefIsCompact = 1,
  };
  DataRefOffsetPtr refOffset;
  template<typename T>
  inline void SetDataRef(T ref);
  template<typename T>
  inline T GetDataRef() const;
  inline bool IsCompact() const;
  template<typename T>
  inline T GetCompactData() const;
  inline intptr_t GetRawValue() const;
  inline void SetRawValue(intptr_t value);
};

// DataRef aims for reference to data in maple file (generated by maple compiler) and is aligned to at least 4 bytes.
// Perhaps MDataRef is more fit, still DataRef is chosen to make it common.
// DataRef allows 4 formats of value:
// 0. "label_name" for direct reference
// 1. "label_name - . + 1" for padding unused
// 2. "label_name - . + 2" for reference in offset format
// 3. "indirect.label_name - . + 3" for indirect reference
//    this format aims to support lld which does not support expression "global_symbol - ."
// DataRef is self-decoded by also encoding the format and is defined for binary compatibility.
// If no compatibility problem is involved, DataRefOffsetPtr is preferred.
enum DataRefFormat {
  kDataRefIsDirect   = 0, // must be 0
  kDataRefPadding    = 1, // unused
  kDataRefIsOffset   = 2,
  kDataRefIsIndirect = 3, // read-only
  kDataRefBitMask    = 3,
};

struct DataRef32 {
  // be careful when *refVal* is treated as an offset which is a signed integer actually.
  uint32_t refVal;
  template<typename T>
  inline T GetDataRef() const;
  template<typename T>
  inline void SetDataRef(T ref, DataRefFormat format = kDataRefIsDirect);
  template<typename T>
  inline T GetRawValue() const;
};

struct DataRef {
  uintptr_t refVal;
  template<typename T>
  inline T GetDataRef() const;
  template<typename T>
  inline void SetDataRef(const T ref, const DataRefFormat format = kDataRefIsDirect);
  template<typename T>
  inline T GetRawValue() const;
};
// GctibRef aims to represent a reference to gctib in maple file, which is an offset by default.
// GctibRef is meant to have pointer size and aligned to at least 4 bytes.
// GctibRef allows 2 formats of value:
// 0. "label_name - . + 0" for reference in offset format
// 1. "indirect.label_name - . + 1" for indirect reference
//    this format aims to support lld which does not support expression "global_symbol - ."
// GctibRef is self-decoded by also encoding the format and is defined for binary compatibility.
// If no compatibility problem is involved, DataRef is preferred.
enum GctibRefFormat {
  kGctibRefIsOffset = 0, // default
  kGctibRefIsIndirect = 1,
  kGctibRefBitMask = 3
};

struct GctibRef32 {
  // be careful when *refVal* is treated as an offset which is a signed integer actually.
  uint32_t refVal;
  template<typename T>
  inline T GetGctibRef() const;
  template<typename T>
  inline void SetGctibRef(T ref, GctibRefFormat format = kGctibRefIsOffset);
};

struct GctibRef {
  uintptr_t refVal;
  template<typename T>
  inline T GetGctibRef() const;
  template<typename T>
  inline void SetGctibRef(const T ref, const GctibRefFormat format = kGctibRefIsOffset);
};

// MByteRef is meant to represent a reference to data defined in maple file. It is a direct reference or an offset.
// MByteRef is self-encoded/decoded and aligned to 1 byte.
// Unlike DataRef, the format of MByteRef is determined by its value.
struct MByteRef {
  uintptr_t refVal; // initializer prefers this field to be a pointer

#if defined(__arm__) || defined(USE_ARM32_MACRO)
  // assume address range 0 ~ 256MB is unused in arm runtime
  // kEncodedOffsetMin ~ kEncodedOffsetMax is the value range of encoded offset
  static constexpr intptr_t kOffsetBound = 128 * 1024 * 1024;
  static constexpr intptr_t kOffsetMin = -kOffsetBound;
  static constexpr intptr_t kOffsetMax = kOffsetBound;

  static constexpr intptr_t kPositiveOffsetBias = 128 * 1024 * 1024;
  static constexpr intptr_t kEncodedOffsetMin = kPositiveOffsetBias + kOffsetMin;
  static constexpr intptr_t kEncodedOffsetMax = kPositiveOffsetBias + kOffsetMax;
#else
  enum {
    kBiasBitPosition = sizeof(refVal) * 8 - 4, // the most significant 4 bits
  };

  static constexpr uintptr_t kOffsetBound = 256 * 1024 * 1024; // according to kDsoLoadedAddessEnd = 0xF0000000
  static constexpr uintptr_t kPositiveOffsetMin = 0;
  static constexpr uintptr_t kPositiveOffsetMax = kOffsetBound;

  static constexpr uintptr_t kPositiveOffsetBias = static_cast<uintptr_t>(6) << kBiasBitPosition;
  static constexpr uintptr_t kEncodedPosOffsetMin = kPositiveOffsetMin + kPositiveOffsetBias;
  static constexpr uintptr_t kEncodedPosOffsetMax = kPositiveOffsetMax + kPositiveOffsetBias;
#endif

  template<typename T>
  inline T GetRef() const;
  template<typename T>
  inline void SetRef(const T ref);
  inline bool IsOffset() const;
};

struct MByteRef32 {
  uint32_t refVal;
  static constexpr uint32_t kOffsetBound = 256 * 1024 * 1024; // according to kDsoLoadedAddessEnd = 0xF0000000
  static constexpr uint32_t kPositiveOffsetMin = 0;
  static constexpr uint32_t kPositiveOffsetMax = kOffsetBound;

  static constexpr uint32_t kPositiveOffsetBias = 0x60000000; // the most significant 4 bits 0110
  static constexpr uint32_t kEncodedPosOffsetMin = kPositiveOffsetMin + kPositiveOffsetBias;
  static constexpr uint32_t kEncodedPosOffsetMax = kPositiveOffsetMax + kPositiveOffsetBias;

  static constexpr uint32_t kDirectRefMin = 0xC0000000; // according to kDsoLoadedAddessStart = 0xC0000000
  static constexpr uint32_t kDirectRefMax = 0xF0000000; // according to kDsoLoadedAddessEnd = 0xF0000000

  static constexpr int32_t kNegativeOffsetMin = -(256 * 1024 * 1024); // -kOffsetBound
  static constexpr int32_t kNegativeOffsetMax = 0;

  template<typename T>
  inline T GetRef() const;
  template<typename T>
  inline void SetRef(T ref);
  inline bool IsOffset() const;
  inline bool IsPositiveOffset() const;
  inline bool IsNegativeOffset() const;
};

// MethodMeta defined in methodmeta.h
// FieldMeta  defined in fieldmeta.h
// MethodDesc contains MethodMetadata and stack map
struct MethodDesc {
  // relative offset for method metadata relative to current PC.
  // method metadata is in compact format if this offset is odd.
  uint32_t metadataOffset;

  int16_t localRefOffset;
  uint16_t localRefNumber;

  // stack map for a methed might be placed here
};

// Note: class init in maplebe and cg is highly dependent on this type.
// update aarch64rtsupport.h if you modify this definition.
struct ClassMetadataRO {
  MByteRef className;
  MethodFieldRef fields;  // point to info of fields
  MethodFieldRef methods; // point to info of methods
  union {  // Element classinfo of array, others parent classinfo
    DataRef superclass;
    DataRef componentClass;
  };

  uint16_t numOfFields;
  uint16_t numOfMethods;

#ifndef USE_32BIT_REF
  uint16_t flag;
  uint16_t numOfSuperclasses;
  uint32_t padding;
#endif // !USE_32BIT_REF

  uint32_t mod;
  DataRefOffset32 annotation;
  DataRefOffset32 clinitAddr;
};

static constexpr size_t kPageSize = 4096;
static constexpr size_t kCacheLine = 64;

// according to kSpaceAnchor and kFireBreak defined in bp_allocator.cpp
// the address of this readable page is set as kProtectedMemoryStart for java class
static constexpr uintptr_t kClInitStateAddrBase = 0xc0000000 - (1u << 20) * 2;

// In Kirin 980, 2 mmap memory address with odd number of page distances may have unreasonable L1&L2 cache conflict.
// kClassInitializedState is used as the init state for class that has no <clinit> method, it's will be loaded in many
// place for Decouple build App. if we set the value to kClInitStateAddrBase(0xbfe00000), it may conflict with the
// yieldpoind test address globalPollingPage which is defined in yieldpoint.cpp.
// Hence we add 1 cache line (64 byte) offset here to avoid such conflict
static constexpr uintptr_t kClassInitializedState = kClInitStateAddrBase + kCacheLine;

extern "C" uint8_t classInitProtectRegion[];

// Note there is no state to indicate a class is already initialized.
// Any state beyond listed below is treated as initialized.
enum ClassInitState {
  kClassInitStateMin = 0,
  kClassUninitialized = 1,
  kClassInitializing = 2,
  kClassInitFailed = 3,
  kClassInitialized = 4,
  kClassInitStateMax = 4,
};

enum SEGVAddr {
  kSEGVAddrRangeStart = kPageSize + 0,

  // Note any readable address is treated as Initialized.
  kSEGVAddrForClassInitStateMin = kSEGVAddrRangeStart + kClassInitStateMin,
  kSEGVAddrForClassUninitialized = kSEGVAddrForClassInitStateMin + kClassUninitialized,
  kSEGVAddrForClassInitializing = kSEGVAddrForClassInitStateMin + kClassInitializing,
  kSEGVAddrForClassInitFailed = kSEGVAddrForClassInitStateMin + kClassInitFailed,
  kSEGVAddrFoClassInitStateMax  = kSEGVAddrForClassInitStateMin + kClassInitStateMax,

  kSEGVAddrRangeEnd,
};

struct ClassMetadata {
  // object common fields
  MetaRef shadow;  // point to classinfo of java/lang/Class
  int32_t monitor;

  // other fields
  uint16_t clIndex; // 8bit ClassLoader index, used for querying the address of related ClassLoader instance.
  union {
    uint16_t objSize;
    uint16_t componentSize;
  } sizeInfo;

#ifdef USE_32BIT_REF // for alignment purpose
  uint16_t flag;
  uint16_t numOfSuperclasses;
#endif // USE_32BIT_REF

  DataRef iTable;  // iTable of current class, used for interface call, will insert the content into classinfo
  DataRef vTable;  // vTable of current class, used for virtual call, will insert the content into classinfo
  GctibRef gctib;  // for rc

#ifdef USE_32BIT_REF
  DataRef32 classInfoRo;
  DataRef32 cacheFalseClass;
#else
  DataRef classInfoRo;
#endif

  union {
    uintptr_t initState; // a readable address for initState means initialized
    DataRef cacheTrueClass;
  };

 public:
  static inline intptr_t OffsetOfInitState() {
    ClassMetadata *base = nullptr;
    return reinterpret_cast<intptr_t>(&(base->initState));
  }

  uintptr_t GetInitStateRawValue() const {
    return __atomic_load_n(&initState, __ATOMIC_ACQUIRE);
  }

  template<typename T>
  void SetInitStateRawValue(T val) {
    __atomic_store_n(&initState, reinterpret_cast<uintptr_t>(val), __ATOMIC_RELEASE);
  }
};

// function to set Class/Field/Method metadata's shadow field to avoid type conversion
// Note 1: here we don't do NULL-check and type-compatibility check
// NOte 2: C should be of jclass/ClassMetata* type
template<typename M, typename C>
static inline void MRTSetMetadataShadow(M *meta, C cls) {
  meta->shadow = static_cast<MetaRef>(reinterpret_cast<uintptr_t>(cls));
}

#endif // METADATA_LAYOUT_H
